The primary objective of the proposal is to support Mayo Clinic's participation in the Children's Cancer Study Group. This will allow continuing support for the cooperative group activities of the Pediatric Oncology Group at Mayo Clinic and its satellites in Des Moines, Iowa; Fargo, North Dakota; and Duluth, Minnesota. The ultimate goal of the proposal is to develop methods for long-term control and cure in a wide variety of malignant diseases in children while evaluating and minimizing the adverse short-term and long-term effects of treatment. Clinical research in pediatric cancer demands a coordinated team effort involving surgeons, therapeutic radiologists, pathologists, pediatric oncologists, immunologists, histochemists, pharmacologists and radiologists. Solid tumor treatment protocols are becoming increasingly more complex and accurate pretreatment staging and standardized operative, radiotherapeutic and chemotherapeutic procedures are essential. Since pediatric surgeons, pediatric urologists and orthopedic oncologic surgeons play a major role in diagnosis, staging and surgical therapy of solid tumor patients and also participate actively in postoperative evaluation, reporting and data analysis, their formal involvement in this program is critical for maintaining the highest level of clinical and laboratory research within the Children's Cancer Study Group. In addition, psychosocial evaluation and support for the patient and family is considered essential to the successful outcome of this type of clinical research and can also provide a basis for the development of clinical research studies for evaluating the psychosocial impact of cancer on children and their families.